Tubular superheater.



W. SCHMIDT. l TUBULAR SUPEEHEATER. APPLICATION FILED MAR. 2, 1909.

Patented Dec. 5, I911 2 SHEETS-SHEET 2.

[Ni 5111708 Q? m 0 H w IITTORIYEVS 4 sinners "sternum un on.

wxnnnrimscnnmr; or wrnnuesrsntinn, HEAE essna, GERMANY.

TUBULAR surn'msnarnn.

Specification of Letters fetent.

Patented Dec. 5,1911.

Application filed fiar h 2, 1969. Serial 150. 480,904.

To all whom it may concern:

Be it known that I, WILHELM Sonium'r, a subject of the King of Prussia, German.

perc -and resident of Wilhelmshohe, near My invention 1 lates to steam superheaters of the eneral haiecter disclosed in patents issueto me previously, and has for its object to secure-improved results as regards I the production of dry superheated steam.

In practice it has. been found difficult to utilize the heat of the heating gases fully and towel them-to the desired degree, for the reason that the highly superheated steam will, through the walls of the tubes through which such steam is conducted, give part of its heat to the heating gases which have been previously cooled by contact we.- ter-cooled surfaces, so that part oi the heat given to the superheated steam is lost by being retra-nsferred to the'cooled heating gases. This, of course, detracts from the efliciency of the superheater.

For the purpose of avoiding the drawback pointed out above, I have, asit'w'erc,

divided the superheating coil through which the steam passes into a plurality of sections. The section through which the steam to be superheated passes firstis exposedto contact with the cooler portion of the heating gases and serves for drying the'wet steam coming from a suitable; collector or chamber.

Another section of the superheating coil, through which the steam passes subse quently, is exposed to the hotter portion of the heating gases, so that the steam is there superheated strongly. As will be seen from the detailed description following hereinafter, this general idea may be carried out in a variety of forms.

be desirable to provide a suitable heat insulator for that'portion of the steam coil or steam tube, which would otherwise be in contact with the cooler portionof the heating gases in order to further prevent the retransfer of heat from the superheated steam to the cooler heating gases. v Reference is to be hadvtothe accompanying drawings in whicht Figure 1 is a'longitudinal section through part of a steam superheater constructed according to my invention Fig. 2 is a cross section on line 2-2 of Fig. 1; Fig. 3 is a In some cases it may.

. j'crorss section on line 33 ef'Fig. 1; Fig. 4: is

in connect-ion withthe lowe'r smoke tube of 1 and Figs. 6, 7 and 8 are further dia- I ginnimatic views forms of myinvention.

Referring particularly to Figs. 1 to 5 9?. indicates a collecting chamber or header, in which the wet steani coming from a-boiler is received. e indicates the plate for receiving the ends of the smoke tubes r through which the heatinggases are supposed to.

travel from left to right to reach the smoke hon f.' From thedistributi-ng chamber '71 the steam passes through superheating coils which are located Within the smoke tube '1'. There as shown in Figs. 1, 2 and 42 the upper smoke tube '1' contains four steam tubes as were, that is to say, a cross-section of said upper smoke tube will show four steam tubes. The steam first passes through a ,U-shaped portion a traveling in the upper member thereof (see Fig. 1.) in a direction opppsitc to that of the combustion gases, and in the lower member thereof inthe same direction with the combustion gases... In this first U-shaped section of the superheating coil, the wet steam becomes dry; it then passes through the portion 9 in a'dircction opposite to that of the combustion gases, t6; the left hand end of the second U-shaped section b: which is of the reverse arrangement to the first section a, that is to say, in the secondsection the'steam first travels in the same direction as the combustion gases and then in the opposite direction. Finally from the upper left-hand end of the section b the steam passes through the portion in the same direction as the heating gases and finally reaches the collecting chamber h from in connection with the lower smoke tube "r' of 1, l. have illustrated a somewhat different arrangement which is also shown in Figs. 3 and 5. Here the steam passes first through two U-shaped sections a, a? which illustrating additional through the pipe. portion are located in the cooler portion of the smoke tube 1", is then conducted through alpipe, portion r to a second section located in a hotter portion of the smoke tube and consistin of two .U-shapcd members 6, b arrange reversely to the tubes orcoils a, (5 Finally the steam passes to the cells I j which maybe partly cover d with a heat insulation-r7 in the same manner as described for the pipe portion j. As shown in Figs. 1 and 3 these various coils arearranged Within the lower smoke tube in such a manner as to show six crosssections of the steam pipe or coil.

it will of course be understood that. the couiplctc super-heater comprises a large number of coils of the character described.

All the coils may be of the same construction as shown in connection'with the upper smoke tube, or they may all be, of the same construction as those Within the lower smoke tube. The arrangement may further be .varied in other'ways, three examples -.of

I sectionbi arranged.

which I have shown in Figs. 6, 7 and 8.

In Fig. 6 four cross sections of the steam pipe are locatedwithin each of the smoke tubes. The steam passes first through a U-shaped section a practically identical with the one shown in Figs. 1, 2 and 4t and is then conducted through a pipe section 0 to a long U-shaped section. d contained in the lower smoke tube r. Then the steam passes through a second section (5 identical with the section (Z and through pipe portions 0, g to a U-shapcd section arranged reversely to the section a and in a hotterportion of the upper smoke tube r. Finally the steam passes to the collecting chamber it throughthe )ipc portionuj In Fig. 7 the arrangement of the pipe portions a, c is the same as in Fig. 6. In the lower tube, however, thesteam passes first through a U-shaped section (Z arranged. only in the cooler portion of said smoke tube, then through a return pipe d and exposed to the hotter heating gases. From there on the path of the steam' 1s the sa'me'as in Fi cl, c", 1 7) and j I I in Fig. 8 the steam coils are arranged to pass through three smoke tubes won their path from the collecting chamber a to'thc collecting chlimber It. The steam first passes through the U-shaped section a, the

connecting pipe portion 0 and the U-shaped section (Z, these three portions being substantially identical in arrangcn'ient with those shown in Fig. 6. Then the steam passes through a connecting pipe portion a and alongitud inal portion rZ-into a U-shaped section located in the third smoke tube a" and exposcdfio the hotter combustion gases therein. 'lhcrcupoii the steam is conducted to the collecting chamber cting chapiber h I g to a U-sh-aped reversely to the section '6 through the pipe sectionsj Another portion of the steam passes 'from the collecting chamber 72 to a U-shaped section (5" located in the lowermost smoke tube rat the cooler portion thercofand arranged rei'ersely to the coil section Z); then through" a connecting portion 6 the steam Jasses thron -h a U-sha Jed section (mm H mined in the second smoke tube and then passes through a connecting pipe portion.

0 to a return pipe g to a U-shaped section f arrangcdin the hotter portion of the upper smoke tube and reversely to the coil section it. Finally through a pipe portion j the'steam is led to the collecting chamber 71. It will be understood that the insulation' i such as indicated in Figs. it to omay also be employed in connection. with the other forms of my inventiom The steam, by being led back and forth so as to travel at times in the direction opposite to that of the heatinggases and at other times in the same direction therewith, will be first dried when exposed to the compare.- tively lesser heat of the heating gases in the portions ofthe smoke tubes nearest to the smo'ke'hox f, and then the dry steam will be superheated chiefly in those portions of the steam coils which are in the hotter parts of the smoke tubes, that is, farther away 'fromthesmoke boxf. I

I claim as my invention:

1. The. combinationin a boiler structurev provided with heating tubes, with one or more of said tubes, of a super-heater located in said tube or tubes and comprising a plural ity of.U-shaped sections connected in series some of said sections being arranged lo'ngitudinally of one another in the same heating tube, as and for the purpose described.

52. The combination with one or' more 195 each tube, a collecting chamber for receiving the steam after its passage through the superheatcr, and an insulating covering on the portion of thesuperheater tube adjacent to said chamber. I

In a fire tube boiler, a superheater element. comprising a plurality oi. U-shaped sections connected in series, at least two of said elements being arranged longitudinally in a single heating tube, and connectin tubes for carrying steam to and from sai sections, the section tubes and the connecting tubes being arranged concentrically with the walls of the heating tube. I

4. The combination of a boiler structure provided with heating tubes through which heating gases are adapted to pass and a superhcater con'iprising a plurality -of U it through a, pipe shaped sections through which steam is seen us 0 adapied in pass successively, ssverai of sai .eing arranged longitudinally ofone another in the same tube with the section through Wilii'fii sisgim passes first nearer the outlier (if its tube than the other :tions, as and. for the purposes dsscribed.

5. The combination of a huiier structure previded with heating tubes through which heating gases are adapted to pass, and a pluraiiiy of superheai'cr elements comprissuch a plurality of SQCtiOIlS arranger ss srsi sections is tube Within such tub the Bastions through which the sieam p first (1 r, p 'ising two 0011x160 is ,d poi-irons through which the steam travels in opposite dire tions, and being located adjacent to the outlet of structure, while the next section sf the s'uperhenrer extends in a portion farther away iii-0m the outlet and therefore expsseci to greater heat.

In iestimony wnereof I have hereunto set my hand in the presence of two subscribing witnesses. I

YVILHE-LM SCHMIDT.

., rin s FBANKE, Msn'rm SUHMIIH. 

